2009 Annual Report - NASA Airborne Science Program

AAFEx
HQ sponsor: Aeronautics Research Mission Directorate
During January and February 2009 the DC-8 was
employed in a ground test series to support the
Alternative Aviation Fuel Experiment (AAFEX)
at the NASA Dryden Aircraft Operations Facility
(DAOF) in Palmdale, California. The rising cost of
oil coupled with the need to reduce pollution and
dependence on foreign suppliers has spurred great
interest and activity in developing alternative aviation
fuels. Detailed studies are required to ascertain the
exact impacts of the fuels on engine operation and
exhaust composition. In response to this need,
NASA acquired candidate alternative fuels from a
variety of sources and burned the fuels in the NASA
DC-8 to assess changes in the aircraft’s CFM-56
engine performance and emission parameters
relative to operation with standard JP-8. The
AAFEX Aeronautics Research Mission Directorate
project managed by Dan Bulzan of NASA Glen
Research Center and under the direction of the
Project Lead Scientist Bruce Anderson of NASA
Langley Research Center, the AAFEX tests sought
to establish fuel matrix effects on: 1) engine and
exhaust gas temperatures and compressor speeds and
pressures; 2) engine and auxiliary power unit (APU)
gas phase and particle emissions and characteristics;
and 3) volatile aerosol formation in aging exhaust
plumes. A secondary goal of the study was to
evaluate the role of ambient conditions in regulating
volatile aerosol emissions. Gas phase measurements
included the standard certification species (CO 2 , CO,
NO x , and THC) along with hydrocarbons, hazardous
air pollutants (HAPS), and oxygenated compounds.
Measured particle parameters included smoke
number; number density, size distribution and total
Figure 30:
Arial view of the AAFEX test setup showing DC-8 in the open-air engine run-up
facility at the Dryden Aircraft Operations Facility in Palmdale, CA.
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